Contact tracing is no substitute for mask wearing.
But carrying a rabbit's foot or a four-leaf clover would be a perfect substitute for that, and a lot less harmful to the bearer too.
CDC, WHO, US Surgeon General, Fauci, Australian health service, et al, in March, agreed that mask wearing by members of the public was not effective in slowing the spread of respiratory viruses, and that it could actually be harmful to people not medically trained.
That was, and is, the sum total of all of the human knowledge on the subject. Science is a slow process, and a paradigm shift like this doesn't happen within a few months (how long it took for all of the above entities to contradict their previous statements). Extraordinary claims require extraordinary proof, as the late great Carl Sagan said, and the idea that COVID is somehow unlike influenza, rhinovirus, cold coronavirus, SARS 1 coronavirus, and MERS coronavirus is an extraordinary claim. So is the assertion they made very early on, that unlike all those other respiratory viruses, this novel virus that we know nothing about absolutely, positively does not spread by aerosol.
The premise of droplets being the main modality of contagion is the basis for the six foot rule and the mask mania. Masks are useless for aerosols, and the evidence is quite clear by now that COVID is just a garden variety coronavirus, like all the others our species has known, and it spreads in the same way, which is to say, by aerosol. You'd have to ask the various "medical" government orgs why they refuse to state that the virus can and does spread by aerosol (airborne) the way that all the other respiratory viruses do.
Without the "it's about the droplet" excuse, we're back to the analogy of a mask (short of N95 or better respirator) to stop a virus being like using a chain link fence to keep mosquitoes out of your yard. If they admitted that the droplet thing was a ruse, they'd have to explain how their mask mandates and having us stand a couple a' meters away from one anothers have been the rule for weeks or months. Aerosols remain in the air for hours, and can be carried by HVAC systems into other rooms or even floors-- six feet isn't going to help you (or others around you), and neither is any mask short of a respirator of N95 or equivalent or better.
Preventing disease is not what masks are for, though... they're to give us a little ritual to carry out to make us think they're doing something about the virus, while demonstrating their subservience to their masters. Every problem calls for more government, right? People have been trained to think so. Despite their nearly perfect record to the contrary, people think governments solve problems, so when the media whips them into a lather with the latest out-of-context doom and gloom (in July, 73% of Americans surveyed thought COVID was getting worse, even though the death rate was by then down 98% from its mid-April peak), they get frightened and demand the government "do something." Mask rules are "something," all right, but "something effective?" No, quite assuredly not.
The virus is a force of nature. It's going to do what it is going to do until it runs its course. You know that little graph they showed when they were explaining what "flatten the curve" meant? Google it if you haven't. It showed the hospitalization rate from a virus like COVID if nothing was done, a curve that rose rapidly to a high peak, then dropped almost as quickly again to baseline. The "flattened" curve showed a slow rise to a peak in about July, and then a slow fall back toward baseline. The dotted line that cut across the highest part of the peak in the "do nothing" curve indicated the peak surge capacity of hospitals, while the flattened curve never crossed that line.
Note that the "do nothing" line didn't just keep rising, nor did it rise to a high level and stay put. It rose, then it fell rapidly. If you look at the death rate in the US (and probably other countries, but I don't know where to find their statistics... this is from the CDC), it rocketed to a peak in mid April, then began a drop that continues even now. There was a small peak in July (which did not show up in the stats until August, as it takes a while for the records to come in) that coincides with the riots/"mostly peaceful" protests, but it's been dropping again for well over a month since then.
From the way the media reports it, you'd think that without heroic measures by government officials, the death rate (and along with it the closely correlated hospitalization rate) would just go up and stay there. The media and pols breathlessly report the increased number of positive tests and imply that each one is virtually a death sentence, but they fail to report that the death rate dropped 98% (as reported by the CDC data from their site). It's not positive tests that made this thing so scary... it's deaths, and deaths are way, way down... but you won't hear that from the media. All you hear is the "this thing ain't goin' away" doom and gloom, even as it is in the process of going away. Despite our best efforts, the thing is in the process of running its course, just like pandemics always do. When you're going through hell, keep going! We keep trying to stop, and then they claim that slowing down will get us to the other side faster, which makes no sense.